[FeFe]-Hydrogenase ([FeFe]-H<sub>2</sub>ase) model compounds have shown promise as potential alternatives to expensive platinum-based catalysts for the reversible oxidation of molecular hydrogen. Catalytic activity can be induced by light but little is known about the long-term thermal and photochemical products that contribute to catalysis. Here, long-term photolysis is examined for the trimethylphosphine and trimethylphosphine hydride derivatives of a common [FeFe]-H<sub>2</sub>ase model compound in coordinating and non-coordinating solvents and under nitrogen and CO. The phosphine coordinated compound has several isomers that contribute to the parent IR spectrum and the ratios of these isomers are solvent dependent. However, the IR changes upon photolysis show that CO loss is the major product in all solvents at a short time scale followed by solvent addition to the open coordination site. These experimental results are supported by density functional theory (DFT) calculations and CO vibrational frequencies. In addition, DFT calculations support major isomerization upon photolysis for the hydride compound.

Photochemical and thermal analysis of phosphine modified hydrogenase model compounds

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.